We have a "whole house fan" in our home. And it was a great investment for us. My husband grew up with that in the South and I've never heard of it in CA, so I was skeptical.
We use it during the summer nights, and when I want to get rid of smoke/smell residue from cooking (I turn it on for 1 hour when I leave the house, and I come back with the smell gone). We did not need HOA approval.
We live 2-3 miles north of the 5FWY, which is hotter than other parts of the city. But we have only used the AC 2x this summer during the nights. It's not really useful during the day time if the outside air is hot.
Our house is 2600 sf, and we bought a double fan system, with automatic timer from amazon (sorry I don't have the info on the product).
We used Direct Electric Company from Murrietta and it was inexpensive for install, they also sell the equipment. I think less than $2K for equipment and install.
http://www.yelp.com/biz/direct-electric-company-murrieta-2?osq=whole+house+fan
FYI, it feels good when I hear my neighbors AC unit running at night and we don't have to. We don't even have to use our ceiling fans at night, as the constant air blowing on my face is bothersome.
BTW, the whole house fan is not that loud, it seems equally or maybe even less noisy than the AC.
Good luck!